Related papers: Theory of barrier vs tilt exchange gate operations…
Scattering or tunneling of an electron at a potential barrier is a fundamental quantum effect. Electron-electron interactions often affect the scattering, and understanding of the interaction effect is crucial in detection of various…
We propose an implementation of the two-qubit gate in a quantum dot spin qubit system which is immune to charge noise problems. Our proposed implementation, if it could be realized in a physical system, would have the advantage of being…
We investigate the effects of spin-orbit interaction (SOI) on the exchange cotunneling through a spinful Coulomb blockaded quantum dot. In the case of zero magnetic field, Kondo effect is shown to take place via a Kramers doublet and the…
Generalized electrostatic quantum swap gate implemented in the chain of 2 double coupled quantum dots using single electron in semiconductor is presented in tight-binding simplistic model specifying both analytic and numerical results. The…
Distributing circuits across quantum processor modules will enable the execution of circuits larger than the qubit count limitations of monolithic processors. While distributed quantum computation has primarily utilized circuit cutting, it…
We consider simulating quantum systems on digital quantum computers. We show that the performance of quantum simulation can be improved by simultaneously exploiting commutativity of the target Hamiltonian, sparsity of interactions, and…
The nature of the exchange coupling variation in an antiferromagnetic spin-1/2 system can be used to tailor its ground-state properties. In particular, dimerized Heisenberg rings containing domain walls have localized states which can serve…
Optimal control theory is a versatile tool that presents a route to significantly improving figures of merit for quantum information tasks. We combine it here with the geometric theory for local equivalence classes of two-qubit operations…
We use spin-density-functional theory (SDFT) ab initio calculations to theoretically explore the possibility of achieving useful gate control over exchange coupling between cobalt clusters placed on a graphene sheet. By applying an electric…
Single-electron pumps based on tunable-barrier quantum dots are the most promising candidates for a direct realization of the unit ampere in the recently revised SI: they are simple to operate and show high precision at high operation…
This paper reviews recent studies of mesoscopic fluctuations in transport through ballistic quantum dots, emphasizing differences between conduction through open dots and tunneling through nearly isolated dots. Both the open dots and the…
Silicon quantum dots are considered an excellent platform for spin qubits, partly due to their weak spin-orbit interaction. However, the sharp interfaces in the heterostructures induce a small but significant spin-orbit interaction which…
In order to enable semiconductor-based quantum computing with many qubits, issues like residual interqubit coupling and constraints from scalable control hardware need to be tackled to retain the high gate fidelities demonstrated in current…
Controlled adiabatic transfer of a single electron through a chain of quantum dots has been recently achieved in GaAs and Si/SiGe based quantum dots, opening prospects for turning stationary spin qubits into mobile ones, and solving in this…
Two-qubit gates between spin qubits are often performed using a rectangular or an adiabatic exchange interaction pulse resulting in a CZ gate. An oscillating exchange pulse not only performs a CZ gate, but also enables the iSWAP gate, which…
As a candidate scheme for controllably coupled qubits, we consider two quantum dots, each doped with a single electron. The spin of the electron defines our qubit basis and trion states can be created by using polarized light; we show that…
Four electron spin qubits in quantum dots are studied by means of an exchange interaction Hamiltonian. The time-independent Schr\"odinger equation is exactly analytically solved for the symmetric case, that is equal qubit frequencies and…
We investigate the behavior of qubits consisting of three electron spins in double and triple quantum dots subject to external electric fields. Our model includes two independent bias parameters, $\varepsilon$ and $\varepsilon_{M}$, which…
Protecting the dynamics of coupled quantum systems from decoherence by the environment is a key challenge for solid-state quantum information processing. An idle qubit can be efficiently insulated from the outside world via dynamical…
Exchange coupled {\it spin} qubits in semiconductor nanostructures are shown to be vulnerable to dephasing caused by {\it charge noise} invariably present in the semiconductor environment. This decoherence of exchange gate by environmental…